Substituted amide-1,4-diacylpiperazine complexes



groups. The substitutedamide compounds which may be em- United States Patent f SUBSTITUTED AMlDE-1,4-DIACYLPIPERAZlNE COMPLEXES Robert 'C. ONeill, New York, N.Y., assignor to Merck Co., Inc., Rahway, N.J., a corporation of New ersey No Drawing. Application October 18, 1956 Serial No. 616,603

4Claims. (Cl. 260-965) This invention relates to novel substituted amide-1,4-

' diacylpiperazine complexes and to the processes for preparing these novel compounds.

It has been found that these substituted amide-1,4- diacylpiperazine complexes possess marked and efiective action in the control and treatment of the disease coccidiosis which infects poultry.

The novel substituted amide-1,4-diacylpiperazine complexes may be represented by the following structural formula RI! wherein R is hydrogen or a lower alkyl group, R is an electron withdrawing group, R" is a member selected from the group consisting of formyl and acetyl groups, and X is oxygen or sulfur.

' The substituted amide-1,4-diacylpiperazine complexes wherein R is hydrogen or a lower alkyl group, R is an electron withdrawing group and X is oxygen or sulfur, witha 1,4-diacylpiperazine represented by the formula RI! wherein R isas defined above and R-,is a member se lected from the group consisting of formyl and acetyl ployed as one of the starting materials in this process are carbanilide compounds having an electron withdrawing group in either or both of the 4 and 4-positions of the rings. Examples of electron withdrawing groups which may be used are nitro, cyano, carboxy, carboalkoxy, acetyl, trimethyl ammonium, sulfonic acid and carbamide groups. Such groups are alternatively referred to as meta directing (see Fieser and Fieser, Organic Chemistry, 2d edition, 1950, page 595). Specific carbanilide compounds which may be employed include 4,4-dinitrocarbanilide; 2-methyl-4,4-dinitrocarbanilide; 4-nitro-4'- cyanocarbanilide; and 4-nitro-4-acetocarbanilide.

.of. the cecum of chickens.

2,881,157 Patented Apr. 7, 1959 The 1,4-diacylpiperazine compounds which may be em. ployed in accordance with this invention include 1,4- diformylpiperazine; 1,4-diacetylpiperazine and 1,4-diacetyI-Z-methylpiperazine.

The specific, and, therefore, unpredictable, nature of the present invention is apparent from the fact that the parent 1,4-diazine itself, i.e., piperazine, is inoperative for the purposes of this invention. Indeed, the unusually specific nature of the R" substituent is further borne out by the fact that the next higher homolog of the 'diacetyl' derivative, i.e., the l,4-dipropionylpiperazine, is also inoperative.

In accordance with one procedure for carrying out th process of this invention, the solid substituted urea compound is reacted with a solution of the 1,4-diacylpiperazine. The reaction mixture in which the substituted urea compound is insoluble or very slightly soluble is stirred until the insoluble complex is formed. Complete ing commences within a few minutes as evidenced by a distinct lightening in color of the suspended solid, and by the substantial increase of slurry. The resulting complex is then filtered, washed and dried.

Ethers such as dioxane and ethyl ether, alcohols such as the lower aliphaticv alcohols, hydrocarbons such as benzene, toluene, water and mixtures of such solvents may be employed satisfactorily. It has been found advantageous to employ a solvent in which the 1,4-diacylpiperazine is soluble and in which the substituted urea is insoluble. I

Alternately, para-nitrophenylisocyanate may be treated with water in the presence of the 1,4-diacy1piperazine. The 4,4'-dinitrocarbanilide thus formed reacts with the 1,4-diacylpiperazine to form the 1,4-diacylpiperazine-4,4- dinitrocarbanilide complex.

As the substituted urea compound it is preferred to employ 4,4'-dinitrocarbani1ide, although, other carbanilides having different electron Wihdrawing groups in the 4 and 4'-positions may be used. Typical substituents which may be present in these positions are nitro, cyano, carboxy and carboalkoxyl radicals. Furthermore, the electron Withdrawing groups of the 4 and 4'-positions need not be the same. Thus typical examples of 4,4-disubstituted carbanilides useful in this invention are 4,4'-dinitrocarbanilide; 4,4-dicyanocarbanilide; and 4-nitro-4i-cyanocarbanilide.

The 1, 4-diacylpiperazine substituted urea complexes prepared in accordance with this invention are active against the widespread poultry disease commonly called coccidiosis which is caused by species of protozoan parasites of the genus Eimeria. In this regard, E. tenella is responsible for a severe and frequently fatal infection Furthermore, other serious infections are caused in fowl by other species of Eimeria and especially E. acervulina, E. necatrix, E. maxima, and E. brunetti. If left untreated, such infections often cause extensive losses' of fowl. The elimination or control of coccidiosis is, therefore, of the utmost importance for successful poultry raising.

According to a further embodiment of this invention, novel compositions useful in the treatment of coccidiosis are provided containing a 1, 4-diacylpiperazine substituted urea complex as an active ingredient. These compositions comprise a 1, 4-diacylpiperazine substituted urea complex intimately combined with an inert carrier. In

this regard compositions which contain a compound of where R, R, R" and X have the same significance as already noted, in a proportion of 2 moles of the substituted urea to 1 mole of the 1, 4-diacylpiperazine, as the active ingredient have been found to be particularly useful 4 B. Ingredients:

(a) 4, 4'-dinitrocarbanilide 1, 4-diacetylpiperazine (b) Corn distillers dried grains Wheat shorts against coccidiosis. 6 (d) Dried vitamin B fermentation solubles e composltwns p p at least one of C0mp0sitz'0n.Each pound of the mixture contains 0.25 d1acylp1peraz1ne subst1tuted urea complexes mentioned pound f coccidiostat above cflmbmed Wlth an P Carmel" b Such Preparation.-The following quantities are employed in compositions are conveniently produced by 1nt1mately order, make 9 pounds f d t: dispersing the active ingredient throughout a carrier. The 10 (a) 250 pounds 4 4u i i b i1i 1 4.di carrier or diluent may be either liquid or solid. Liquid piperazine d1spers1ons can be prepared satisfactorlly by using emulsl- (b) 188 pounds om distiller dried grains (through fiers and surface actlve agents. Any solid can be used 30 mesh Screen) as a carrier which is inert toward the active compounds (c) 487 pounds wheat shorts (30-80 mesh) and which can be administered to ammals with safety. (d) 70 Pounds dried vitamin B12 fermentation solnbles Examples of su1table earners are ground oyster shells, 3 3 mesh) attapulgus clay and edible vegetable materials such as products such as the above are Suitable for ineorntn commerclal anfmal and P y d f corn ration into poultry feedstufis in order to obtain the desired ground corn, citrus meal, fermentatlon residues and (115- dosagelevel f active drug. fillers dnefl actlve mgredfent is conveniently The amount of active ingredient required for effective p f b m a solltd camel y cbnvebtlonabmetbbds Such prophylactic control of coccidiosis is very low. With as f tumbbng, f g tbls a by regard to poultry, good results have been obtained by the sblectlbg d lfle1:611t f and X glib-17mg the {atlo of administration of a quantity of the active ingredient equal U actlve mgredlent, p en of y g wnwnto about .005 to .05% of the food consumed. Optimum PP can be Preparedcbmpbslblc'ns Very Sultable for results are usually obtained by the daily administration addltlon t0 P y feed y from about 5% to of a quantity of active ingredient equal to about .0075% about 40% of tbb new cbcbldlostat, and Pf y about to about .025 of the food consumed. Such relatively 1025 adsorbed pup; mIXed h a small amounts ma be convenientl incorporated in the Premlxes f 4 -d1n1tr0carban1hde 1, Y P P normal ration prior to feeding the poultry. Larger conazmb y be P P as referred 9 above 111 a e centrations of up to about 0.1% of the active ingredient manner. Two satlsfactory formulations are described in may be employed therapeutically if an outbreak of the deta11 below. disease is encountered. A. Ingredients: The coccidiostatic activity of compositions containing fi i e 1, 4-diacetylp1perazine various 1,4-diacylpiperazine substituted urea complexes complex t I was experimentally demonstrated according to the fol- (b) Corn distillers dried grams lowing test: Wbeflt b Groups of 10 two-week chicks were fed a mash feed (d) r 1ed vltamm B12 fermentau? Solubles containing from 0.01% to 0.04% of the active ingredient 'P P 9? of the mlxture Preparatlbn uniformly dispersed therein. After existing on the contains 0.30 pound of coccldlostat drug. In order to me diet for 24 hours each chick was inoculated with 50,000 pare 1000 pounds of feed prem1x the followlng quant1t1es Spnrnlnted eoeysts of tenella. In addition groups of are gg d 4 b d 1 4 t l 10 chicks were also infected but fed a diet free of the g l Penn 5 lmtrocar e lacey active ingredient and used as positive controls. Still other groups were treated separately with the substituted gl gg ggg com dlstluers dried grams (through urea compound and the 1,4-diacetylpiperazine compound (c) 455 pounds wheat shorts (30-80 mesh) and 3 g g i of i substlmtecit f f (d) 70 pounds dried vitamin B fermentation solubles Polin an e lacy P1P erazme q q 6 ex- (30 80 mesh) perlment was termlnated after admmlstermg the respec- The total amounts f Wheat shorts and fermentation t1ve d1ets for seven days after inoculation and the folsolids, and about 150 pounds of corn grains are mixed lowmg r were Obtamed- Tb obeyst count (P followed by the drug and the remainder of the corn grains. of P 0f tenella f determmed y After mixing for about two hours the material is ready for Sacrificing blfds and examlnlflg the Infected Organs packaging. miscroscopically. The results are given in Table I.

TABLE I. ANTIOCOCCIDIAL TESTING RESULTS Percent Mortality Oocyst Count Percent Weight Percent X10 Gain Compound Compound InDiet Treated Un- Treated Un- Treated Untreated treated treated 0.1 0 40 20 34 so 45 4,4' dinitrocarbanfl1de 0.05 0 40 28 34 66 45 0.025 20 40 29 34 54 45 0. 0062 5 23 10. 2 1o. 0 35 10 4,4 -dinltrocarbanilide 1,4'diaee- 0. 0125 0 23 0. 5 16. 0 44 16 tylpiperazine complex. 0. 025 0 19 0. 1 15. 1 46 22 0.1 0 10 0.1 12.8 9 at '88i a a at as a 2 4,4 dinitroearbanilldo-L4 ditor- I I 4 1 mylpiperazine complex. g g 2 0. 05 0 3 0.1 29.7 43 28 0. 0062 25 2a 7.6 18.6 31 11 4,4 dinitrocarbanilide 1,4-diaeeo. 01 0 1s 11. a 20. 7 40 12 tyl-2-methylpiperazine com- 0.0125 0 23 2.2 18.0 48 10 lex. 0. 025 0 25 0. 1 16. 5 46 10 0.05 o 23 0.1 17.0 43 2 It will be noted from Table I that 4,4'-dinitrocarbanilide when administered separately does have activity, but such activity does not approach that displayed by the complex. The 1,4-diacylpiperazines are inactive.

The following examples are intended to be illustrative only and may be varied or modified without departing from the spirit and scope of this invention.

Example I.4,4'-dinitrocarbanilide-I,4-diacetylpiperazine complex Nine and thirty-five hundredths (9.35) grams (0.055 mole) of diacetylpiperazine was dissolved in a mixture of methanol (50 ml.) and ether (50 ml.) at room temperature (about 25 G). Then 15.1 grams (0.05 mole) of 4,4'-dinitrocarbanilide was added with stirring.

Complexing commenced within a few minutes as evidenced by a distinct lightening in color of the suspended solid, and by the substantial increase in viscosity of the suspension.

The slurry was stirred overnight at room temperature, and the greenish yellow complex was collected by filtration, washed with ether, and dried to constant weight.

The yield of the 4,4-dinitrocarbanilide-1,4-diacetylpiperazine complex, in the ratio of 2 moles of the carbanilide to 1 mole of the substituted piperazine was 18.4 grams, or 95% of theory.

0n analysis-Calculated for C H O N C, 52.7; H, 4.38; N, 18.08. Found: C, 52.72; H, 4.40; N, 18.43.

Example lI.-4,4-dinitr0carbanilide-1,4-diformylpiperazine complex 0 H-c=o U I NB NB N OsN N0: N

NH EN H l i' o Gabi U ON 09 A slurry of 15.6 g. of N,N'diformylpiperazine (JACS, 77, 753, 1955), 30.2 g. of dinitrocarbanilide and 200 ml. of methanol was stirred at room temperature for eight hours. The solid material was removed by filtration and rinsed once with methanol. The dry complex weighed 35 g. and melted and decomposed about 290-295.

Analysis.-Calculated for cggHgoNsomcgHmNzoai C, 51.47; H, 4.05. Found: C, 50.89; H, 4.40.

The complex is composed approximately of 2 moles of dinitrocarbanilide and one mole of diformylpiperazine.

Example 1II.-4,4'-dinitrocarbanilide 1,4-diacetyl-2- methylpiperazine complex To 20 g. of Z-methylpiperazine was added 100 ml. of acetic anhydride. The mixture was heated under reflux for three hours and then the solvent was distilled ofl at about 70 mm. pressure. The residue was crystallized from ethyl acetate to give N,N-diacetyl-2-methylpiperazine, M.P. 1l8-ll9.

Analysis.Calculated for cgHmNgog: C, 58.67; H, 8.75. Found: C, 59.25; H, 9.18.

A slurry of 30.2 g. of 4,4'-dinitrocarbanilide, 20.2 g. of N,N'diacetyl-2-methylpiperazine and 150 ml. of methanol was stirred at room temperature for nine hours. The product was removed by filtration and rinsed once with methanol to give 36.4 g. M.P. about 275285.

Analysis.-Calculated for C H N O -C H N O C, 53.30; H, 4.60. Found: C, 53.12; H, 4.29.

The complex is composed approximately of 2 moles of dinitrocarbanilide and one mole of diacetyl-Z-methylpiperazine.

Various changes and modifications may be made in carrying out the present invention without departing from the spirit and scope thereof. Insofar as these changes and modifications are within the purview of the annexed claims, they are to be considered as part of this invention.

What is claimed is:

1. A chemical complex of and wherein R is selected from the group consisting of hydrogen and a lower alkyl group, R is an electron withdrawing group selected from the group consisting of nitro, cyano, carboxy, carboalkoxy, acetyl, trimethyl ammonium, sulfonic acid and carbamide radicals and R" is selected from the group consisting of formyl and acetyl groups.

2. 4,4 dinitrocarbanilide- 1,4 diacetylpiperazine complex.

3. 4,4"dinitrocarbanilide- 1,4 diformylpiperazine complex.

4. 4,4 dinitrocarbanilide-1,4 diacetyl 2 methylpiperaz'me complex.

References Cited in the file of this patent Cuckler et al.: Science, 122, 244-5 (1955). 

1. A CHEMICAL COMPLEX OF 